Promising Research in Early Detection of Mesothelioma
PRWEB, January 9, 2006
Mesothelioma, once a rare cancer, has become more prevalent in the past 50 years. The incidence of this aggressive disease, which has no cure, is expected to rise through 2015.
Until recently, mesothelioma was considered universally fatal. Patients treated with the best available therapy have survived 13 to 25 months in some studies, and with only supportive care the median survival is about 9 months. Studies investigating the diagnosis of mesothelioma have recently reported promising results, which may help reverse this tragic trend.
If caught before spreading beyond the lungs, there is a much greater chance of successfully treating the disease. Once mesothelioma has spread, the disease quickly overcomes its victim. With earlier detection, current treatments would be more effective, more aggressive treatment could be developed and life expectancy could rise dramatically.
One of the challenges of treatment for mesothelioma patients is the inability to detect the aggressive cancer in its early stages. Unfortunately, mesothelioma is very challenging to diagnose until the advanced stages. Because the onset of disease is delayed for as much as 30 years beyond exposure, symptoms are vague and the diagnostic tools are not efficient or specific, many cases are not diagnosed until the disease is advanced.
To date, screening through serial chest x-rays and pulmonary function testing has not been effective in detecting the disease in its earlier stages. While some asbestos related disease has been detected, these methods cannot differentiate between mesothelioma and benign lung disorders. Computer tomography (CT) can detect even small tumors, but also does not distinguish between malignant lesions and benign lung changes. Thus, the stumbling block to early diagnosis is distinguishing early stage cancer from other lung problems.
Biomarkers, or naturally occurring chemicals that can be detected in the blood have been linked to many specific cancers. Studies have shown a link between the substance TPA and mesothelioma, but this correlation had not yet been proven. Ca 125, a known marker for ovarian cancer has also shown promising but unconfirmed results in detecting early stage mesothelioma.
According to a recent article published in the December 2005 New England Journal of Medicine, a recent study of the protein osteopontin produced encouraging results. Comparing patients diagnosed with mesothelioma, patients exposed to asbestos but disease free and healthy control subjects, revealed clear differences in the patients with malignant disease. Although more research is needed to confirm the accuracy of this investigation, a strong correlation between osteopontin levels and mesothelioma was found.
A significantly higher concentration of osteopontin was detected in patients with diagnosed cases of mesothelioma compared to subjects with asbestos exposure. When compared, the levels of osteopontin were not significantly different in unexposed control subjects versus those subjects exposed to asbestos. Nearly 78% of mesothelioma patients showed elevated osteopontin levels. Levels were elevated in both patients with early stage disease (Stage I) and advanced disease. In over 85% of cases, osteopontin levels differentiated patients with mesothelioma versus benign lung conditions.
Definitive detection of mesothelioma in the earlier stages makes surgical removal of tumors possible before the disease has had a chance to spread. Once spread occurs, the effectiveness of surgical treatment drops dramatically. In end?stage disease, suurgery is simply a palliative measure to improve breathing capability with little of no curative value.
While it is not clear that this information will lead to longer survival, we do know that the earlier treatment can begin, the better chance for a prolonged life expectancy and with time, hopefully a cure.